Means for mixing air and gas



Oct. 25, 1938. 5 JQNES 2,134,253

MEANS FOR MIXjNG AIR AND GAS Filed June 27, 1935 2 Sheets-Sheet 1 45 Z5 3; 4'4 75 Z6 45 z/ grvut nto'b 20 I r JSWL PJoAew MEANS FOR MIXING AIR AND GAS Filed June 27, 1955 2 Sheets-Sheet 2 f /9 P0497 Z5 50 I 11 Z7 5% 50 4/ Z5 57 55 5 z? 4 5/ -Z/ 5/ 57 j/ Z7 w x0 52 jZ Z1111): YMOD fam P JOAQJ' Patented Oct. 25, 1938 UNITED STATES 2,134,253 MEANS FOR MIXING Am AND GAS Sam P. Jones, Dallas, Tex., assignor of fortyiper cent to E. W. Schadek, Dallas, Tex. f

Application June 27, 1935, Serial- No. 28,676

1 Claim. (01. 48-180) 7 This invention relates to new and useful improvements in means for mixing air and gas.

One object of the invention is to provide an improved gas mixer for gas engines, which is operated by the suction of the engine, whereby the gas and air is correctly proportioned and controlled by the suction of the engine to maintain highest efliciency under all conditions.

An important object of the invention is to prolflvide an improved air and gas mixer for engines having a movable piston which is actuated by the suction of the engine for controlling the inlet of air and gas and also having a spring for returning the piston to its cut-01f position, the mixer including a pressure actuated member which is connected with the piston and exposed to the suction of the engine, whereby an increased exposed area for moving the piston against the spring tension is had, which permits the piston to so be moved by a lower suction which detracts less from the H. P. of the engine; the increased ex-- posed area also allowing a stronger return spring to be employed which assures positive return of the piston to its cut-ofi position.

Another object of the invention is to provide a gas mixer for gas engines having a movable piston exposed to the suction of the engine for controlling the fiow of gas and air therethrough and including a pressure actuated member which is exposed to the suction of the engine through restricted passages whereby fluttering of the piston in operation is prevented.

Another object of the invention is to provide an improved gas mixer, wherein a movable piston is employed for controlling the flow of gas and air into the engine, said mixer having means for increasing the richness of the mixture when the engine is accelerated or an increased load imposed thereon and decreasing the richness of said mixture when the load on the engine decreases or when the engine is slowed down, whereby the mixer may be applied to an engine operating under widely variable loads.

Still another object of the invention is to pro vide an improved gas mixer having a movable piston actuated by the suction of the engine for proportioning the air and gas entering the engine, which is so constructed that air at atmospheric pressure may be introduced behind the piston to aid the suction in operating saidpiston, whereby less suction is required to operate the piston which makes for increased efficiency in the operation of the engine.

A further object of the invention is to provide an improved gas mixer including a piston which isrotatablym-oun-ted to control the flow of gas and air through the mixer and having means ior easily and quickly rotating the piston to adjust the flow and then looking the same positively in its adjusted position, the adjusting s means being simple in construction and arranged to :be operated by one hand.

'A still further object of the invention is to provide a diaphragm which is connected with the movable piston of a gas mixture and which no is exposed 'to the suction of the engine, whereby the diaphragm will aid in operating the piston which allows operation of the piston with less suction, the diaphragm being connected to the mixer by removable retaining rings held in place it by a resilient ring so that assembling and dis-P mantling of the entire mixer is ssimplified for purposes of cleaning or for :any other reason. 7

Another object of the invention is 'to provide an improved method cry-mixing air and gas for no use in gas engines whichiincludes introducing gas into ;a. chamber and then introducing air circumferentially into said chamber around the gas, whereby a correct proportion lot gas and air to make a. proper mixture for normal operation 5 of the engine is had, and automatically varying the proportion of gas-and air to provide a richer mixture. when the engine :is accelerated. .or an increased loadis imposed thereon, and. automatically varying the proportion of gas and air when 30 the engine is slowed down or the;load thereon decreased.

A construction designed to carry out the invention will be hereinafter described, together with other ifeaturesiof theinvention. 35

The invention will ibe more readily understood from :a reading of the following specification and byreference :to the accompanying drawings, in which an example of the invention is shown, and wherein:

Figure 1 is a side elevation :of a gasmixenconstructed in accordance with the invention,

Figure '2 is a plan 'view of. the-same,

Figure :3 :is a transverse, vertical sectional view, taken on the line is-I3 =of 2,

Figure 4 is a transverse, vertical sectional view, takenon the line 4-4 of Figure 2,

Figure :5 is va. horizontal, cross-sectional view, taken on the line S -.5 of Figure 1,

Figure 6 is ahor-izontal, cross-sectional view, so taken on the line 6-6 of Figure 1,

Figure 7 is a horizontal, cross-sectional view, taken on the line llo-fl of Figure 1,

Figure -8 is a horizontal, cross-sectional view, taken on the line of Figure l, l5

view showing the connection between the piston and diaphragm,

Figure 10 is an enlarged sectional detail showing the operating lever for the retaining rings, and

Figure 11 is an enlarged plan view of said operating lever.

In the drawings, the numeral l0 designates the housing of a gas, mixer, which has a general cylindrical shape and which may be cast of one piece of metal, or other suitable material. The usual attaching flange H is provided at the upper end of the housing, and a cylindrical bore |2 extends axially therethrough.

In the upper or neck portion of the housing a butter-fly valve I3 is mounted to swing on a diametrically extending shaft "which is journaled in the side wall of the housing. One end of the shaft extends through the wall and has a throttle lever l5 secured thereto. The lever has a stop Hi and a set screw H for engaging a stud |8 on the housing, whereby the swinging of the butterfly valve is limited, as is the usual practice in the art. 7

The bottom of the housing is open and an external annular flange l9 extends around this open end. The upper end of said flangeis beveled as clearly shown in Figure 10. A circular diaphragm case 20 is provided with an annular flange 2| at its upper end which is of the same diameteras the flange I9 and which is arranged to fit thereagainst. The top of the case is reduced whereby an annular shoulder 22 is formed and this reduced portion snugly engages in the openbottom of the housing with the shoulder 22 in engagement with the lower end of the bore |2 to close the lower end .of said bore. With the top of the case closing the bore, it will be seen that the upper end of theflange 2| of the case snugly engages the underside of the flange l9. For securing the case to the housing, a split retaining ring 23 comprising sections A and B is provided. As'shown in Figure 10, the innercontour of said ring is such that a lower annular flange 24 engages under the flange 2| of the case while an upper flange 25 having a complementary bevel engages over the bevel flange I9 01: the housing. The outer surface of the ring is formed with an annular groove 26 which receives a circular spring 21. The spring exerts its tension to force and hold the sections of the ring into close engagement with the flanges l9 and 2| to hold the case and housing together. As shown in Figures 7 and 11, the ends of the sections A and B do not meet at one side of the housing but are cut off to form a space 28. Within this space, an operating lever 29 is located.

The lever is pivoted on a stud 29' which is journaled in the diaphragm case (Figure 10) and it is obvious that the sides of said lever engage the ends of the sections A and B. When the lever is in the position shown in full lines in Figure 11, the spring 21 holds the sections A and .B in tight frictional engagement with the flanges l9 and 2|, whereby the case is rigidly secured to the housing and-is incapable of rotating with the relation thereto. However, when the lever is swung to the position shown in dotted lines, (Figure 11) it will be seen that it spreads the sections A and B of the ring 23.to move the same away from the outer periphery of both the flanges I9 and 2 under tension of the spring 21. This spreading is comparativelyslightand does not disengage the flanges 24 and 250i the ring from the flanges l9 and 2|, but merely breaks the tight frictional engagement between the ring 23 and flanges, whereby rotation of the diaphragm case 23 with relation to the housing l0 may be accomplished, as will be hereinafter explained.

A piston, or piston valve 30 is mounted to slide vertically within the bore |2 of the housing. The piston has an axial stem 3| which extends downwardly through the upper end of the'diaphragm case 20 and is secured to the center of a suitable diaphragm 32 by a nut 32. A sleeve 3| surrounds the stem 3| between the diaphragm and piston and this sleeve serves to space the parts 1 from each other. The lower end of the stem is formed with an integral extension 33 which depends therefrom, through the bottom of the diaphragm case. The lower end of the extension is threaded to receive a wing nut 34 and a coiled spring 35 surrounds the extension being confined between the bottom of the case and said nut, The'spring constantly exerts its tension to hold the piston and diaphragm in a lowered position.

It is pointed out that the suction of the engine to which the mixer is attached acts upon the piston to raise the same.

In order to utilize this suction so that it may also act upon the area of the diaphragm to provide an increased lift area, communication is established between the diaphragm case above the diaphragm 32 andthe area above the piston. To establish such communication, the bottom of the piston is provided with a plurality of ports 36 which encircle the stem 3|. These ports communicate with an annular, vertical passage 31 which is formed between the sleeve 3| and an enlarged sleeve 38 which is slidably mounted in an opening 39 in the top of the diaphragm case 20. The enlarged sleeve is of substantially the samelength as the sleeve 3| but it is noted that saidsleeve 38 is not secured to either the bottom of the piston or the top of the diaphragm although it is confined therebetween. The lower end of the sleeve 38 is provided with openings 40 which communicate with the space above the diaphragm, and thus, it will be seen that the engine suction above the piston will act upon the diaphragm through the ports 36, passage 31 and openings 40. acts upon the cross-sectional area of the piston,

the provision of the diaphragm provides an in-.

by the suction must. act gradually upon the diaphragm. Therefore, fluttering of the piston during lifting of the piston is eliminated as the same moves up gradually. If desired, a flanged washer 30', having openings in its upper end may be located over the ports 36. Brass, wool,

or similar substance is confined within the washerto prevent a backfire of the engine from igniting an explosive mixture, if such mixture was present in the diaphragm case. This washer, however, is not essential.

The piston 30 is provided with a rectangular gasport 4| (Figures 3 and 6) at its lower end.

Thus, since the suction still Above the gas port the piston has an annular air opening or slot 42 which is continuous-except for narrow webs 43 which are cut-back from the piston surface, so as not to contact the bore I2. A nipple 44 is preferably made integral with the housing near its lower end and is threaded to receive a gas inlet pipe 45. At the inner endof the nipple a rectangular gas inlet port 46 is formed. An annular continuous air inletslot 41 extends through the wall of the housing I0 above the nipple and this slot is enclosed by acircular flared hood '48 which is made integral with the outside air inlet 49. (Figure 5.)

The gas ports 4| and 46 in the piston and housing at the innerend of the nipple are of equal height and the air slots 42 and 41 are also of equal width. The air openings-and gas openings are spaced equally from each other in both the piston and housing, consequently both are opened in proportion to each other. In other words, when the air slot 42 begins to register with the air inlet slot 41, the gas ports 4| and 46 come into registration.

'The'inter'ior of the piston 30 has a vertical riser pipe '50 which extends through the bottom of the piston and has its upper end terminating adjacent the air inlet slot 42. Thus, air may pass downwardly through said pipe and enter the space 5| between the underside of the piston and the top of the diaphragm case 20. The; upper end of the pipe is internally threaded to receive a removable plug 52. A radial port 53 is formed in the housing In at the lower end thereof and this port establishes communication between the atmosphere and the space 5| below the piston.

This port is internally threaded and is preferably of the same diameter as the pipe 50, whereby the plug 52 may be interchanged between the port and pipe. As will be explained, either one or the other is plugged.

When the engine, to which the mixer is attached, is stopped, the spring 35 which is under tension (Figures 1, 3 and 4), will pull the piston downwardly to its closed position, whereby the gas ports 47 and 46 and the air slots 42 and 4| are out of registration. In order to effectually close the gas port 46, and prevent gas leakage, the piston 30 is given a loose sliding fit in the bore i2, so that it may undergo a limited lateral movement therein. A wedge key 54 is made integral with the top of the diaphragm case 26 extending upwardly therefrom. This key engages a complementary inclined slot 55 (Figure 3) formed in the piston. When the piston is pulled downwardly by the spring it is shifted laterally by the key, which is located substantially diametrically opposite the gas inlet port 46. This forces the wall of the piston into intimate contact with the wall of the bore |2 surrounding the port 46, thereby sealing oif said port. It is noted that when the piston is in its lowered position, it is resting on the wedge-shaped key, there being the space 5| between the piston and top of the case 26, whereby the lateral displacement of the piston is assured.

When the piston is laterally displaced as above described, the upper end of the stem 3| and sleeve 3| are also displaced. This causes a distortion of the flexible diaphragm but since the lateral movement is so slight, this distorting is practically negligible. The bottom of the piston will slide laterally on the upper end of the enlarged sleeve 38 and since it is slidably mounted in the opening 39 in the diaphragm case it will not interfere with this lateral movement.

When it is desirable to shift the gas ports 4| and 46 with relation to each other wherebythe amount of gas flowing therethrough is 'changed, it is only necessary to rotate the diaphragm case 20 which will rotate the piston through the medium of the wedge key 54 in constant engagement with the slot55 in the piston. To rotate the diaphragm case, the lever 29 is swung to loosen the frictional engagement of the sections A and B of the split retaining ring 23,. as has been explained, after which the case may be easily rotated to make the adjustment. It is pointed out the lever maybe swung wi-th the thumb while the case 20 is engaged by the fingers so that the adjustment maybe made with one hand. As soon as the lever is released, the spring 21 will immediately move-the split ring 23 into tight frictional engagement. v

The arrangement of the split retaining ring not only makes for easy adjustment and positive holding when in adjusted positions but also pro: vides for easy dismantling of the device for cleaning or other purposes. To dismantle the mixer, the spring 21 is rolled upwardly out of the groove 26 in the ring .so as toencircle the lower end of the housing H1. 'The split ring 23 is then removed and the diaphragm case 26 and piston may be removed. The entire operation is but a matter of a few seconds. The .assembling is just as simple.

Assuming that the engine to which. the gas mixer is applied is to be operated under an even load and at a substantially fixed speed,rtheplug 52 isinserted in the .pipe 50 Within the piston. This leaves the radial port 53 in the housing wall below the nipple 44 open, whereby air under atmospheric pressure may. enter the space 5| be; low the piston '30. v

The throttle valve l3 is opened and the engine started. The suction of the engine reduces the pressure above the piston and air at atmospheric pressure which has entered the space 5| below said piston through the opening 53, serves to raise the piston upwardly. Then suction will also act upon the upper face of the diaphragm 32 through the ports 36, passage 31 and opening 46. The increased area upon which the suction may act reduces the amount of suction necessary to raise the piston and therefore less power will be taken from the engine. As the piston raises, the

gas ports 4| and 46 and air slots 42 and 4'! move into registration to admit the proper propotion of gas and aii to the engine (not shown).

It is obvious that since the gas enters at the bottom of the piston some of this gas will enter the diaphragm case above the diaphragm 32 through the passage 31 and ports 46 and this space above the diaphragm forms a gas chamber 38'. This occurs when the mixer is inoperative or when the engine is slowed down, whereby this gas is stored in the gas chamber 38' above the diaphragm. Thus, when the engine is started the diaphragm moves upwardly .and forces this accumulated gas upwardly into the piston to make a richer mixture at starting and accelerating. Similarly, as the engine slows down, some gas is drawn back into the diaphragm case by the downward movement of the piston, whereby the mixture is thinned as the engine idles down. As described above, with the plug 52 in the pipe 50, the mixer is applied to an engine which is operating under a substantially constant or uniform speed or load, whereby there is little change in the position of the diaphragm when the engine is running.

However, when the mixer is employed with an speed, the plug 52 is removed from-the pipe 50 and screwed intothe port 53 to close the same. Thus, when the engine is started andthe piston and diaphragm begins their upward movement, air from the inlet 49 enters the pipe 50 and flows into the space i below the: piston. This air is under a pressure below atmospheric because it is subjected to the engine suction. Therefore'the pressure of this air is equal to the pressure of the air of the piston, whereby the piston is balanced. Thus, the suction acting upon the diaphragm causes the same to move upwardly raising the piston. Therefore, with the plug 52 in the opening 53, the diaphragm does all'the lifting. Since the engine is operating under variable loads, ac'

celeration thereof must be had. Each time, the engine is accelerated, the piston and diaphragm move upwardly, whereby the diaphragm forces additional gas which has beenstored above the diaphragm into the piston to make a richer mixture at the time of acceleration. This gives the engine a more rapid pickup. As the engine slows down or the load thereon decreases the diaphragm and piston move downwardly. This permits gas to flow back into the case 20 and at the same time forces the air in the space 5| upwardly through the pipe 50 into the piston. The introduction of this air together withthe release of gas into the diaphragm case makes for 'a lean mixture as the engine idles down, which is exactly thetime when such mixture is desirable. Thus,

it is seen that maximum efiiciency of the engine is had under all conditions. The interchangeability of the plug 52 between the pipe 50 and port 53 may be accomplished quickly and easily, whereby the device may be applied to an engine operating under any condition.

It is again pointed out that the provision of the retaining ring not only permits a quick and easy adjustment of the case 20 with relation to the housing, but further forms a rigid connection between the housing and case. Also, assembling and dismantling of the entire device can be readily accomplished without removing the housing from the engine to which it may be fastened.

What I claim and desire to secure by Letters Patent is:

A gas mixer including, a housing having gas and air inlets, a piston slidable in said housing arranged to be operated by the suction of an engine and having gas and air inlets located to register with the inlets of the housing when the piston is slid, a diaphragm case communicating with the interior of the piston to permit gas to fiow from the piston to the chamber, a retaining ring engaging the case and housing for securing the case to the housing, resilient means for holding theretaining ring in frictional engagement with the case and housing to prevent rotation of the former with relation to the latter, means for loosening said retaining ring for permitting such rotation, and a diaphragm within the case connected with the piston and exposed to the suction of the engine through a restricted passage whereby an increased area is exposed to the suction toefiect actuation of the piston with less suction, the connection between the'piston and diaphragm causing the latter to be actuated with the piston, whereby said diaphragm forces the gas in the case into the piston to increase the richness of the mixture.

SAM P. JONES. 

